April 18, 2023, 5:06 pm | Read time: 4 minutes
One of the most common image formats is JPG or JPEG. But is there actually a difference between these two terms?
Cute cat photos or a quick snapshot of a delicious meal at a restaurant–social media is full of such images. With a smartphone, it only takes a few seconds, and the most beautiful memory is saved forever on the memory card or in the cloud. Anyone who later takes the time to properly sort their pictures will often encounter the file extension “.jpeg” or “.jpg.” This is the most common image format. We explore why this is the case and why there are two extensions for one image format in this article.
JPEG stands for “Joint Photographic Experts Group.” This international organization developed the JPEG image format in 1992. Since the official name, ISO/IEC 10918-1 or CCITT Recommendation T.81, sounds a bit cumbersome, the members simply chose the name of their own organization: JPEG.
Why is JPEG so popular as an image format?
To understand why JPEG has become a universal image format, we look back at the early days of the computer industry. In the 1980s, there were already computers with graphical user interfaces. However, photos were difficult to display on early computers.
That’s why standardization experts put their heads together to create a suitable image format. JPEG took the lead. The JPEG image format made it possible to display photorealistic images on the monitors of the time.
This works because JPEG uses lossy compression. What does that mean? Certain areas are removed from the original image. However, these are very small and therefore not visible to humans. These tiny ‘holes’ or pixels are compensated for by color points. Thus, the image looks like the original when viewed on the screen.
However, it is only a compressed copy. And here’s the catch: A JPEG image can only be enlarged to a limited extent. That’s the price for lossy compression. But it doesn’t matter because the advantages outweigh the disadvantages.
How the Zip Format Became a Global Standard
The 5 Best Digital Cameras Compared
Is JPEG only for amateur photographers?
Of course, professional photographers in the digital age prefer uncompressed image formats. These are best for later editing.
However, professionals also like to use the JPEG image format because of its small file size. The compression makes it easy to send images as email attachments. JPEG is perfectly adequate for viewing on a screen.
Additionally, the JPEG image format stores information such as the location of the shot or the time it was taken, known as Exif data. This helps with organizing the images later.
JPEG also offers many advantages for websites. Although the format cannot be enlarged arbitrarily, the degree of compression can be manually adjusted. This is useful when a website needs to display a lot of photos. It reduces the page’s loading time.
By the way, if you use the free image editing software GIMP, the software asks about compression before exporting to the JPEG format. You can also check boxes to decide whether to save Exif data, previews, or the color profile, for example.
What is the relationship between JPG and JPEG?
To stay on topic: JPEG and JPG are the same format. The omitted ‘E’ comes from the early days of computing. Before operating systems like Windows had a sleek graphical user interface, everything was controlled via the DOS level. This, in turn, only recognized file extensions with three letters.
To ensure JPEG images appeared on old computers, the JPEG organization dropped the ‘E.’ This extension has persisted to this day. Most JPEG images end up as “.jpg” on computers.
Other formats from these DOS relics exist, such as HTM or HTML, MPG or MPEG, and TIF or TIFF. However, there is indeed a whole JPEG family. Known variants include JPE or JFIF, or in DOS format: JIF.